Motor vehicle tail lamp assemblies conventionally include a housing which contains a plurality of bulb sockets for turn signals, tail lights and stop lights. The lamp housing is conventionally of die cast metal or injection-molded plastic and has a plurality of integral mounting projections which extend from the forward surface thereof and are adapted for insertion through mating apertures of the motor vehicle body panel to which the lamp assembly is to be mounted.
The prior art lamp assemblies are conventionally attached to the body panel as shown in FIG. 2 by the provision of an externally threaded stud having one end threadedly engaged in the integral mounting projection of the lamp housing. The lamp assembly is attached to the body panel by a plurality of nuts which are threadedly engaged on the studs subsequent to their insertion through the body apertures.
A shortcoming of the aforedescribed prior art tail lamp mounting arrangement is that the external threads on the mounting stud are susceptible to a rasping interference with the walls of the body apertures unless the lamp assembly is perfectly aligned with the apertures during assembly and disassembly. Because such a precise alignment is difficult to achieve in the real world of vehicle assembly as well as disassembly and reassembly for vehicle service, it has been found necessary to enlarge the dimension of the apertures in the vehicle body so that the tail lamp assembly may be assembled and disassembled with relative ease. However, it has been found that oversizing the body apertures permits the lamp assembly to be assembled in an imperfect or tilted position.